1. Field of the Invention
This invention relates to glass fiber reinforced acetal polymer mixtures and composites having excellent mechanical properties, e.g., tensile and flexural strength. These compositions are intended for the production of articles requiring particularly high levels of such properties, e.g. spin gears for washing machines and windshield wiper pivots.
2. Description of Related Art
The following information is disclosed in accordance with the terms of 37 CFR 1.56, 1.97 and 1.98.
Crystalline acetal polymers reinforced with glass fibers are commercially produced and sold by the assignee, Hoechst Celanese Corporation.
U.S. Pat. No. 3,639,192, issued Feb. 1, 1972 to Burg et al., discloses for use as adhesives copolymers of formaldehyde or trioxane with 1 to 60% by weight, preferably 1 to 30% by weight, of a cyclic ether, cyclic and/or linear acetal, e.g., 1,3-dioxolane, and/or an alkyl glycidyl formal, polyglycol diglycidyl ether, or bis (alkane triol) triformal. Example 5 discloses a terpolymer of 97.95 wt.% of trioxane, 2 wt.% of ethylene oxide, and 0.05 wt.% of 1,4-butanediol diglycidyl ether (BDGE).
U.S. Pat. No. 3,337,507, issued Aug. 22, 1967 to Gutweiler et al., teaches the formation of high molecular weight copolymers obtained by polymerizing a mixture of trioxane and any of certain polyformals. Example 4 of the patent shows the use of a polyformal which is a clear highly viscous oil at 70.degree. C. obtained by polymerizing a mixture of 1/3 mole of trioxane and 1 mole of dioxolane in the presence of p-nitrophenyl-diazonium fluoroborate as catalyst.
U.S. Pat. No. 4,788,258, issued Nov. 29, 1988 to Collins et al., discloses and claims low Tg acetal copolymers of trioxane and 65 to 75 mol % of 1,3-dioxolane, which are non-crystalline at room temperature and are useful as blending and adhesive agents for conventional, normally crystalline acetal polymers. Also disclosed are blends of the foregoing polymers containing glass in the form of filaments or strands which can be sized or otherwise combined with coupling agents.
U.S. Pat. No. 4,652,594, issued Mar. 24, 1987 to Auerbach et al., discloses glass fiber reinforced oxymethylene polymer molding compositions in which the glass fibers and oxymethylene polymer are coupled with an amino resin.
Japanese Kokai Sho 42-22,065 of Yamaguchi et al., published Oct. 30, 1967, discloses copolymers of trioxane and an aperiodic ring compound, e.g., 1,3-dioxolane, prepared in liquid sulfur dioxide, and in Example 1 shows a copolymer of trioxane and 64 mol % of 1,3-dioxolane.
Pending application Ser. No. 243,381, filed Sep. 12, 1988 by Collins et al., now U.S. Pat. No. 4,898,925, discloses and claims elastomeric copolymers of 15 to 45 mol % of trioxane, 55 to 85 mol % of dioxolane and a small amount of BDGE or butadiene diepoxide, which are non-crystalline at room temperature, and states that such copolymers are useful as adhesive agents for conventional crystalline acetal polymers and other materials, e.g. glass. The entire disclosure of this application is incorporated by reference.
Pending application Ser. No. 255,569 filed Oct. 11, 1988 by Collins et al., now U.S. Pat. No. 4,954,400, discloses and claims bonded articles, e.g., of conventional crystalline acetal polymers and other materials such as glass, wherein the bonding agents are elastomeric, normally non-crystalline terpolymers of the type disclosed in previously cited application Ser. No. 243,381, now U.S. Pat. No. 4,898,925.